Two weeks ago, JRuby 1.7.0 was officially released. Here are a few reasons why you might want to upgrade: Bug fixes JRuby 1.7.0 fixes many compatibility issues with ruby 1.9. Also, JRuby 1.6.8 is no longer being maintained so fixes from 1.7.0 are not getting backported. Support for invokedynamic JRuby 1.7.0 supports the invokedynamic instruction, a new feature in Java 7 which allows the compiler to use duck typing. This means dynamic languages on the JVM will be compiled to faster code. Kernel#exec JRuby 1.7.0’s exec function is now a true system exec that replaces the current process, while previously it spawned a new process and waited until the process exited. Overview I just upgraded my project from 1.6.8 to 1.7.0. It was fairly easy - I took about a day to upgrade our project. Install JRuby 1.7.0 Bundle Tweak Profit! Detailed How-To Install jruby-1.7-0. It's as simple...